Creating game models for android
Often, when you make a model for a computer game, you start out by making a high poly model. Then, from this, you make a lowpoly model that is going to be used inside the game. This is almost always a manual process and it is called retopology. After that you can bake both diffuse texture, ambient occlusion and normals from the highpoly to the lowpoly texture. You will find many many tutorials on this.

In your case, you already have the highpoly model. So do a lowpoly version and start baking.

There are numerous ways to create the lowpoly version.


Create the lowpoly mesh from scratch, extrude new vertices and snap them to the faces of the highpoly version. Fill with faces.
Create a grid of new vertices, and use the shrinkwrap modified to make them fit the highpoly model.
CGCookie have a plugin for this, Retopoflow (previous contours-retopology): https://cgcookiemarkets.com/all-products/retopoflow/
BSurfaces allows you to paint with strokes to create the lowpoly model.
The decimate modifier can automaticly reduce the complexity of a highpoly model. But almost always it must be manually corrected with one of the other methods.
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A quick youtube search found this (looks ok):
http://www.youtube.com/watch?v=eaqYqkjimD8

Blender cookie have many tutorials on this subject, but not all are free:
http://cgcookie.com/blender/page/2/?s=retopology&amp;s_type=tutorials

A super fast tutorial on making a highpoly model super lowpoly:

Step 1. Make your lowpoly model match the outline of the highpoly. Like this:



Step 2. Simple UV-unwrap of the lowpoly (go into edit mode, select all faces and hit U). Mark appropriate edges as seams with Ctrl-E to cut it up. Assign a new image to it.


Step 3. Bake normals to the lowpoly texture like this. Select highpoly, also select lowpoly (select the lowpoly last). Set settings like in the screenshot and hit bake. Save the image as the normal map.


Step 4. Change Bake mode to AO and hit bake again. Save out image.


Final result when combining these two maps into one material in blender. Of course, this will require a shader with a normal texture, but I am pretty certain that JME has it.


This mini-tutorial is very short but it should make you search for more help (or ask questions) on more specific topics (like: how to UV-unwrap a model).

As for your other question. I don't know of any technique to make this more automated.

The dolphin submarine is of my making.